// ==UserScript==
// @name         YouTube Download Manager
// @namespace    https://vietcat.dev/
// @version      1.3
// @description  Download YouTube Premium videos via custom Hugging Face API with CSP-safe DOM handling.
// @author       vietcat
// @match        https://www.youtube.com/watch*
// @grant        GM_xmlhttpRequest
// @grant        GM_addStyle
// @connect      vietcat-remotedownloader.hf.space
// ==/UserScript==

(function () {
  'use strict';

  const API_BASE = 'https://vietcat-remotedownloader.hf.space';
  const state = {
    tasks: [],
    cookies: ''
  };

  function createUI() {
    const container = document.createElement('div');
    container.id = 'yt-download-popup';

    const box = document.createElement('div');
    box.style.background = '#202020';
    box.style.color = 'white';
    box.style.padding = '10px';
    box.style.borderRadius = '8px';
    box.style.width = '300px';

    const cookieToggleBtn = document.createElement('button');
    cookieToggleBtn.textContent = '🛠️ Cookie Settings';
    cookieToggleBtn.style.marginBottom = '6px';
    cookieToggleBtn.style.display = 'block';

    const cookieInput = document.createElement('textarea');
    cookieInput.placeholder = 'Paste your Netscape-format cookies here';
    cookieInput.style.width = '100%';
    cookieInput.style.height = '100px';
    cookieInput.style.display = 'none';
    cookieInput.addEventListener('input', () => {
      state.cookies = cookieInput.value.trim();
      updateDownloadButtonState();
    });

    cookieToggleBtn.addEventListener('click', () => {
      cookieInput.style.display = cookieInput.style.display === 'none' ? 'block' : 'none';
    });

    const button = document.createElement('button');
    button.id = 'yt-start-download';
    button.textContent = '📥 Download Video';
    button.style.padding = '6px 12px';
    button.style.background = '#ff0000';
    button.style.color = 'white';
    button.style.border = 'none';
    button.style.borderRadius = '5px';
    button.style.cursor = 'pointer';
    button.disabled = true;

    const list = document.createElement('div');
    list.id = 'yt-download-list';
    list.style.marginTop = '10px';

    box.appendChild(cookieToggleBtn);
    box.appendChild(cookieInput);
    box.appendChild(button);
    box.appendChild(list);
    container.appendChild(box);
    document.body.appendChild(container);

    GM_addStyle(`
      #yt-download-popup {
        position: fixed;
        top: 10px;
        left: 10px;
        z-index: 99999;
      }
      #yt-download-list .item {
        background: #333;
        padding: 8px;
        border-radius: 6px;
        margin-top: 6px;
        font-size: 12px;
      }
      #yt-download-list .item a {
        color: #00ffcc;
        text-decoration: none;
        display: inline-block;
        margin-top: 4px;
      }
      #yt-download-list .item button {
        margin-top: 4px;
        background: transparent;
        color: white;
        border: 1px solid #555;
        border-radius: 3px;
        padding: 2px 6px;
        cursor: pointer;
      }
    `);

    button.addEventListener('click', startDownload);
  }

  function updateDownloadButtonState() {
    const btn = document.getElementById('yt-start-download');
    btn.disabled = !state.cookies;
  }

  function updateList() {
    const list = document.getElementById('yt-download-list');
    while (list.firstChild) list.removeChild(list.firstChild);

    state.tasks.forEach(task => {
      const el = document.createElement('div');
      el.className = 'item';

      const title = document.createElement('div');
      const strong = document.createElement('strong');
      strong.textContent = task.shortUrl;
      title.appendChild(strong);
      el.appendChild(title);

      const status = document.createElement('div');
      status.textContent = `Status: ${task.status}`;
      el.appendChild(status);

      if (task.status === 'done') {
        const a = document.createElement('a');
        a.href = task.downloadUrl;
        a.target = '_blank';
        a.download = '';
        a.textContent = '⬇️ Download';
        el.appendChild(a);
      }

      const remove = document.createElement('button');
      remove.textContent = '❌ Xoá';
      remove.addEventListener('click', () => {
        state.tasks = state.tasks.filter(t => t.id !== task.id);
        updateList();
      });

      el.appendChild(remove);
      list.appendChild(el);
    });
  }

  function startDownload() {
    const url = location.href;
    const shortUrl = url.split('?')[0].replace('https://www.', '').replace('youtube.com/watch', 'yt');
    const taskId = Date.now().toString();

    state.tasks.push({ id: taskId, shortUrl, status: 'downloading...', downloadUrl: '' });
    updateList();

    const encodedCookie = btoa(state.cookies);

    GM_xmlhttpRequest({
      method: 'POST',
      url: `${API_BASE}/download`,
      headers: { 'Content-Type': 'application/json' },
      data: JSON.stringify({ url, cookie: encodedCookie }),
      onload: (response) => {
        try {
          const json = JSON.parse(response.responseText);
          const task = state.tasks.find(t => t.id === taskId);
          if (json.download_url) {
            task.status = 'done';
            task.downloadUrl = `${API_BASE}${json.download_url}`;
          } else {
            task.status = 'error';
          }
        } catch (e) {
          const task = state.tasks.find(t => t.id === taskId);
          if (task) task.status = 'failed';
        }
        updateList();
      },
      onerror: () => {
        const task = state.tasks.find(t => t.id === taskId);
        if (task) task.status = 'error';
        updateList();
      }
    });
  }

  const waitForReady = setInterval(() => {
    if (document.body && !document.getElementById('yt-download-popup')) {
      clearInterval(waitForReady);
      createUI();
    }
  }, 1000);
})();